I really want to marry my high school boyfriend after college (and he does too), but we're heading off to different colleges?

I've known this guy since 9th grade but we didn't start dating until June, 2019 (before my junior year). It started as a crush, then friends, and then dating. This spring/summer, I realized that I am in love with him. He's my first boyfriend, yes, and I'm his first real girlfriend, but I truly think that's what I'm feeling: love. This sounds so cliché, but there's not many guys like him. He's extremely caring, empathetic, smart, and kind to me, his parents, siblings, friends, everyone. He's the guy who'll be partners with the lonely kid in the back. He's such an interesting and talented person. We are attracted to each other physically, but also at a much deeper level. We're able to have open conversations with each other about anything. Everyone around us says that there's something special about us. 

We both really don't want to breakup before college (he said this the other day), but we know we may have to because long distance is hard. I just can't see myself dating anyone else because I'm still in love. What if that feeling never goes away? Is there a chance we could reconnect after college? But what if I meet another guy? What am I supposed to do? 

Has anyone ever been here before? Thank you.
(Part of me was OK with the idea of breaking off before college and still remaining friends, but now, even if we go to separate colleges, I know that we'll want to be a part of each others' lives, whether it's marriage or as friends. I don't want to lose him completely.)